JP6911645B2 - Physical quantity sensor, manufacturing method of physical quantity sensor, composite sensor, inertial measurement unit, portable electronic device, electronic device and mobile body - Google Patents

Description

The present invention relates to a physical quantity sensor, a method for manufacturing a physical quantity sensor, a composite sensor, an inertial measurement unit, a portable electronic device, an electronic device, and a mobile body.

Conventionally, as a method of detecting acceleration as a physical quantity, a physical quantity sensor that is configured according to the rocker lever principle and detects acceleration from a capacitance that changes with acceleration applied in the vertical direction has been known. For example, Patent Document 1 discloses a physical quantity sensor composed of a movable body provided with a movable electrode portion, a beam portion supporting the movable body portion, and a fixed electrode arranged to face the movable electrode portion on a substrate. There is. The physical quantity sensor needs to prevent the movable body from swinging (displaced) significantly when an excessive acceleration is applied due to a drop impact of a device equipped with the physical quantity sensor, causing the movable body to collide with the substrate and be damaged. There is. The physical quantity sensor described in Patent Document 1 is provided with protrusions on a substrate (support substrate) for limiting the displacement of the movable body.

On the other hand, the physical quantity sensor is devised to improve the detection sensitivity of acceleration. For example, in the physical quantity sensor described in Patent Document 2, when a movable body is displaced toward a substrate on which a fixed electrode is arranged, a drag force due to air generated between the movable body and the substrate (squeeze film damping: hereinafter, damping). In order to reduce (described as), an opening was provided to penetrate the movable body.

Japanese Unexamined Patent Publication No. 2013-185959 U.S. Pat. No. 8,806,940

Since the physical quantity sensor described in Patent Document 1 is not provided with an opening for reducing damping in the movable body, the detection sensitivity of acceleration is low. Further, the physical quantity sensor described in Patent Document 2 is provided with an opening on the entire surface of the movable body, and the protrusion described in Patent Document 1 is provided on the support substrate of the physical quantity sensor to limit the displacement of the movable body. In this case, there is a problem that the frame portion of the movable body is easily damaged when the grid-like frame portion formed by the adjacent openings and the protrusion are locally contacted. That is, it has been difficult to provide a physical quantity sensor with improved detection sensitivity and reliability.

The present invention has been made to solve at least a part of the above-mentioned problems, and can be realized as the following forms or application examples.

[Application Example 1] The physical quantity sensor according to this application example has a flat plate shape, has a plurality of openings in a direction penetrating the flat plate surface, and has a movable body that can swing around a rotation axis. When the support substrate connected to a part of the flat plate surface by a support column and the support substrate are viewed in a direction perpendicular to the flat plate surface in order to support the movable body with a gap from the flat plate surface. In the above, when the support substrate is viewed in the direction perpendicular to the flat plate surface, including a protrusion provided so as to project toward the movable body in a region overlapping the movable body of the support substrate with a gap. In the above, when the maximum external dimension of the protrusion is D, the opening is provided in a region excluding the range of D / 2 from the outer periphery of the protrusion toward the outside.

According to this application example, the movable body of the physical quantity sensor has a plurality of openings in the direction of penetrating the flat plate surface. In the movable body, a part of the flat plate surface and the support substrate are connected by columns, and the movable body is supported at a distance from the support substrate. When the support substrate is viewed in the direction perpendicular to the flat plate surface, a protrusion protruding toward the movable body is provided in a region overlapping the movable body of the support substrate. When the maximum external dimension of the protrusion is D, the opening of the movable body is provided in a region other than the range of D / 2 from the outer circumference of the protrusion to the outside. In other words, the region where the movable body swings and the movable body and the protrusions come into contact with each other is not provided with an opening, so that the rigidity of the region is improved. As a result, when an excessive acceleration is applied to the physical quantity sensor and the movable body comes into contact with the protrusion, it is possible to prevent the movable body from being damaged. Further, since the movable body is provided with an opening in a region other than the range of D / 2 from the outer circumference of the protrusion to the outside, damping of the movable body is reduced and the sensitivity for detecting a physical quantity is improved. Therefore, it is possible to provide a physical quantity sensor with improved reliability and detection sensitivity.

[Application Example 2] In the physical quantity sensor described in the above application example, it is preferable that a plurality of the protrusions are provided.

According to this application example, a plurality of protrusions protruding from the support substrate toward the movable body side are provided. As a result, the impact received when the movable body and the protrusion come into contact with each other can be dispersed.

[Application Example 3] In the physical quantity sensor described in the above application example, it is preferable that the protrusions are provided symmetrically with respect to the center line that divides the movable body into two equal parts in the axial direction of the rotation axis.

According to this application example, the protrusions protruding from the support substrate toward the movable body are provided symmetrically with respect to the center line that divides the movable body into two equal parts in the axial direction of the rotation axis. As a result, it is possible to prevent the movable body from being damaged due to the twisting of the movable body when the movable body and the protrusion come into contact with each other.

[Application Example 4] In the physical quantity sensor described in the above application example, the protrusion is within 1/2 of the distance between the rotation axis and the end of the movable body in a direction intersecting the axial direction of the rotation axis. It is preferable that it is provided.

According to this application example, the protrusion protruding from the support substrate toward the movable body is provided within 1/2 of the distance between the rotating shaft and the end of the movable body in the direction intersecting the axial direction of the rotating shaft. .. The damping received by the movable body increases toward the end of the movable body. Therefore, it is possible to reduce the damping received by the movable body by forming the region having no opening corresponding to the protrusion on the rotation shaft side where the influence of damping is small.

[Application Example 5] The method for manufacturing a physical quantity sensor according to this application example is a flat plate shape, has a plurality of openings in a direction penetrating the flat plate surface of the flat plate shape, and is movable around a rotation axis. A support substrate connected to a part of the flat plate surface by a support column in order to support the body and the flat plate surface of the movable body with a gap, and the support substrate in a direction perpendicular to the flat plate surface. When viewed, the support substrate includes a protrusion provided so as to project toward the movable body in a region overlapping the movable body with a gap thereof, and the support substrate is provided in a direction perpendicular to the flat plate surface. When viewed, when the maximum external dimension of the protrusion is D, the opening is a method for manufacturing a physical quantity sensor provided in a region excluding the range of D / 2 from the outer periphery of the protrusion toward the outside. A support substrate forming step of forming the support substrate and the protrusion, a substrate bonding step of joining the support substrate and the silicon substrate, and a movable body forming step of forming the movable body having the opening from the silicon substrate. It is characterized by including.

According to this application example, the manufacturing method of the physical quantity sensor includes a support substrate forming step of forming a support substrate and protrusions, a substrate bonding step of joining the support substrate and the silicon substrate, and forming a movable body having an opening from the silicon substrate. It includes a movable body forming step. First, in the support substrate forming step, a space (cavity) in which the movable body can swing and a protrusion are formed in the cavity. Next, in the substrate bonding step, the silicon substrate, which is the raw material of the movable body, is bonded to the support substrate. Then, in the movable body forming step, the outer shape and the opening of the movable body are formed. In the manufacturing method of this application example, an opening is formed after forming a cavity in the support substrate.

On the other hand, as a method for manufacturing a physical quantity sensor, there is a method in which a silicon substrate on which a sacrificial layer is formed and a support substrate are joined via the sacrificial layer to form a cavity in the sacrificial layer in which a movable body can swing. In this manufacturing method, after forming a movable body on a silicon substrate, a sacrificial layer is etched from an opening formed in the movable body. Therefore, it is necessary to provide an opening in the movable body without a gap.

In the manufacturing method of this application example, a silicon substrate is joined after forming a cavity to form a movable body and an opening. As a result, when the support substrate is viewed in the direction perpendicular to the flat plate surface, when the maximum external dimension of the protrusion is D, an opening is provided in a region excluding the range of D / 2 from the outer circumference of the protrusion to the outside. Can be configured. In other words, it is possible to make a configuration in which an opening is not provided in the area where the movable body and the protrusion come into contact with each other. As a result, the rigidity of the area where the movable body and the protrusion contact is improved, so that damage to the movable body can be suppressed when the movable body and the protrusion come into contact with each other due to excessive acceleration applied to the physical quantity sensor. can. Further, since the movable body is provided with an opening in a region other than the range of D / 2 from the outer circumference of the protrusion to the outside, damping of the movable body is reduced and the sensitivity for detecting a physical quantity is improved. Therefore, it is possible to provide a method for manufacturing a physical quantity sensor with improved reliability and detection sensitivity.

[Application Example 6] The composite sensor according to the present application example is characterized by including the physical quantity sensor and the angular velocity sensor element described in the above application example.

According to this application example, the composite sensor can be easily configured, and for example, acceleration data and angular velocity data can be acquired.

[Application Example 7] The inertial measurement unit according to this application example includes a physical quantity sensor according to any one of the above application examples, an angular velocity sensor, and a control unit that controls the physical quantity sensor and the angular velocity sensor. It is characterized by.

According to this application example, it is possible to provide a highly reliable inertial measurement unit by means of a physical quantity sensor having improved impact resistance.

[Application Example 8] The portable electronic device according to this application example includes the physical quantity sensor according to any one of the above application examples, a case in which the physical quantity sensor is housed, and a case in which the physical quantity sensor is housed in the physical quantity sensor. It is characterized by including a processing unit for processing output data from the case, a display unit housed in the case, and a translucent cover that closes an opening of the case.

According to this application example, it is possible to provide a highly reliable portable electronic device with further improved control reliability by using the output data of the physical quantity sensor with improved impact resistance.

[Application Example 9] The electronic device according to the present application example is characterized by including the physical quantity sensor described in the above application example and a control unit that controls based on a detection signal output from the physical quantity sensor. And.

According to this application example, it is possible to provide an electronic device provided with a physical quantity sensor having improved sensitivity and reliability for detecting a physical quantity.

[Application Example 10] The moving body according to the present application example is characterized by including the physical quantity sensor described in the above application example and a control unit that controls based on a detection signal output from the physical quantity sensor. And.

According to this application example, it is possible to provide a moving body provided with a physical quantity sensor having improved sensitivity and reliability for detecting a physical quantity.

The plan view which shows typically the physical quantity sensor which concerns on embodiment. FIG. 1 is a cross-sectional view taken along the line AA in FIG. The cross-sectional view which shows the operation of the physical quantity sensor schematically. The cross-sectional view which shows the operation of the physical quantity sensor schematically. The cross-sectional view which shows the operation of the physical quantity sensor schematically. The cross-sectional view which shows the operation of the physical quantity sensor schematically. The flowchart explaining the manufacturing process of a physical quantity sensor. Cross-sectional view of each manufacturing process of the physical quantity sensor. Cross-sectional view of each manufacturing process of the physical quantity sensor. Cross-sectional view of each manufacturing process of the physical quantity sensor. Cross-sectional view of each manufacturing process of the physical quantity sensor. Cross-sectional view of each manufacturing process of the physical quantity sensor. The plan view which shows typically the physical quantity sensor which concerns on a modification. FIG. 13 is a cross-sectional view taken along the line BB. A functional block diagram showing a schematic configuration of a composite sensor. An exploded perspective view showing a schematic configuration of an inertial measurement unit. The perspective view which shows the arrangement example of the inertia sensor element of an inertial measurement unit. The plan view which shows typically the structure of the portable electronic device. The functional block diagram which shows the schematic structure of the portable electronic device. The perspective view which shows the schematic structure of the mobile type (or notebook type) personal computer as an electronic device which includes a physical quantity sensor. The perspective view which shows the schematic structure of the mobile phone (including PHS) as an electronic device provided with a physical quantity sensor. The perspective view which shows the schematic structure of the digital still camera as an electronic device which includes a physical quantity sensor. A perspective view schematically showing an automobile as a moving body equipped with a physical quantity sensor.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each of the following figures, the scale of each layer and each member is different from the actual scale in order to make each layer and each member recognizable in size.
Further, in FIGS. 1 to 6 and 8 to 14, for convenience of explanation, three axes, an X-axis, a Y-axis, and a Z-axis, which are orthogonal to each other, are shown, and the tip side of the arrow showing the axial direction is shown. The "+ side" and the base end side are the "-side". Further, in the following, the direction parallel to the X-axis is referred to as "X-axis direction", the direction parallel to the Y-axis is referred to as "Y-axis direction", and the direction parallel to the Z-axis is referred to as "Z-axis direction".

(Embodiment)
<Structure of physical quantity sensor>
FIG. 1 is a plan view schematically showing a physical quantity sensor according to an embodiment. FIG. 2 is a cross-sectional view taken along the line AA in FIG. First, the schematic configuration of the physical quantity sensor 100 according to the embodiment will be described with reference to FIGS. 1 and 2. In FIG. 1, the lid 30 is not shown for convenience of explanation.

The physical quantity sensor 100 of the present embodiment can be used as, for example, an inertial sensor. Specifically, for example, it can be used as an acceleration sensor (capacitance type acceleration sensor, capacitance type MEMS acceleration sensor) for measuring acceleration in the vertical direction (Z-axis direction). In the present embodiment, the vertical direction is referred to as the Z axis, the axial direction of the rotation axis (beam portion 25) described later is referred to as the Y axis, and the direction intersecting both the Z axis and the Y axis is referred to as the X axis.

As shown in FIGS. 1 and 2, the physical quantity sensor 100 has a flat plate shape, and has a movable body 20 having a flat plate surface 28, a support substrate 10 for supporting the movable body 20, and a movable body 20 together with the support substrate 10. The included lid 30 is included.

The support substrate 10 has a concave cavity 16. A first fixed electrode 11 and a second fixed electrode 12 are provided on the main surface 17 in the cavity 16. Further, between the first fixed electrode 11 and the second fixed electrode 12, a support column 14 for supporting the movable body 20 with a flat plate surface 28 at a distance is provided. Further, protrusions 15 protruding toward the movable body 20 side (+ Z axis side) are provided on both sides of the support column 14 in the X-axis direction. The support column 14 and the protrusion 15 are formed integrally with the support substrate 10. The material of the support substrate 10 is not particularly limited, but in the present embodiment, borosilicate glass (hereinafter referred to as glass), which is an insulating material, is adopted as a preferable example.

The first fixed electrode 11 is located on the −X-axis side of the support column 14 in the side view from the Y-axis direction, and is provided in a region overlapping the first mass portion 21 described later in the plan view from the Z-axis direction. ing. The second fixed electrode 12 is located on the + X-axis side of the support column 14 in the side view from the Y-axis direction, and is provided in a region overlapping the second mass portion 22 described later in the plan view from the Z-axis direction. There is. Examples of the materials of the first and second fixed electrodes 11 and 12 include Pt (platinum), Al (aluminum), Mo (molybdenum), Cr (chromium), Ti (titanium), Ni (nickel), and Cu (copper). ), Ag (silver), Au (gold), or a conductive film such as ITO (Indium Tin Oxide) can be adopted.

The movable body 20 includes a support portion 24 and a beam portion 25 as a rotation axis. The support portion 24 is a part of the flat plate surface 28, and is connected to the support substrate 10 by a support column 14. The beam portion 25 is supported by the support portion 24 and extends from the support portion 24 in the Y-axis direction. The beam portion 25 has a function as a so-called torsion spring. The beam portion 25 oscillatingly supports the entire movable body 20 with respect to the support substrate 10 via the support portion 24 and the support column 14.

The movable body 20 has a first movable body 20a and a second movable body 20b. The first movable body 20a is a region on the -X axis direction side from the center line CL2 which is the center of rotation of the beam portion 25, and the second movable body 20b is a region from the center line CL2 which is the center of rotation of the beam portion 25 to the + X axis. This is the area on the directional side. The first movable body 20a is provided with a first mass portion 21 and a third mass portion 23 in order from the beam portion 25 in the −X axis direction. The second movable body 20b is provided with a second mass portion 22. In a plan view from the Z-axis direction, the first mass portion 21 is located in a region overlapping the first fixed electrode 11, and the second mass portion 22 is located in a region overlapping the second fixed electrode 12.

The material of the movable body 20 is not particularly limited, but in the present embodiment, silicon, which is a conductive material, is adopted as a preferable example. By using a conductive material for the movable body 20, the first mass portion 21 and the second mass portion 22 can have a function as electrodes. A non-conductive substrate may be used for the movable body, and the first and second mass parts may be formed by a conductive electrode layer provided on the non-conductive substrate.

The movable body 20 is supported by the beam portion 25 and can swing around the beam portion 25 as a rotation axis. When the movable body 20 swings (tilts) with the beam portion 25 as a fulcrum, the gap (distance) between the first mass portion 21 and the first fixed electrode 11 and the second mass portion 22 and the second fixed electrode are The gap (distance) with 12 changes. The physical quantity sensor 100 has a capacitance C1 generated between the first mass portion 21 and the first fixed electrode 11 and between the second mass portion 22 and the second fixed electrode 12 according to the tilt of the movable body 20. , C2 changes to find the acceleration.

When a vertical acceleration (for example, gravitational acceleration) is applied to the movable body 20, a rotational moment (force moment) is generated in each of the first movable body 20a and the second movable body 20b. Here, when the rotational moment of the first movable body 20a (for example, a counterclockwise rotational moment) and the rotational moment of the second movable body 20b (for example, a clockwise rotational moment) are balanced, the movable body 20 There is no change in the inclination of, and the acceleration cannot be detected. Therefore, when the acceleration in the vertical direction is applied, the rotational moment of the first movable body 20a and the rotational moment of the second movable body 20b are not balanced, and the movable body 20 is tilted so as to cause a predetermined inclination. Is designed.

The physical quantity sensor 100 arranges the beam portion 25 at a position deviated from the center of gravity of the movable body 20 in the X-axis direction. In other words, since the first movable body 20a is provided with the third mass portion 23, the distance Ra from the center line CL2, which is the rotation axis of the beam portion 25, to the end face of the first movable body 20a, and the center line. The distance Rb from CL2 to the end face of the second movable body 20b is different. As a result, the first movable body 20a and the second movable body 20b have different masses from each other. That is, the mass of the movable body 20 is different between one side (first movable body 20a) and the other side (second movable body 20b) starting from the center line CL2 of the beam portion 25. By making the masses of the first movable body 20a and the second movable body 20b different in this way, the rotational moment of the first movable body 20a and the second movable body 20a generated when the movable body 20 is accelerated in the vertical direction. The rotational moment of the movable body 20b can be imbalanced. As a result, when the physical quantity sensor 100 is subjected to vertical acceleration, the movable body 20 tilts.

A capacitance (variable capacitance) C1 is formed between the first mass portion 21 and the first fixed electrode 11. Further, a capacitance (variable capacitance) C2 is formed between the second mass portion 22 and the second fixed electrode 12. The capacitance of the capacitance C1 changes according to the gap (distance) between the first mass portion 21 and the first fixed electrode 11, and the capacitance C2 is the second mass portion 22 and the second fixed electrode 12. The capacitance changes according to the gap (distance) with.

For example, when the movable body 20 is horizontal to the support substrate 10, the capacitances C1 and C2 have capacitance values that are substantially equal to each other. Specifically, in a plan view from the Z-axis direction, the overlapping area of the first mass portion 21 and the first fixed electrode 11 and the overlapping area of the second mass portion 22 and the second fixed electrode 12 are equal, and Y When viewed from the side from the direction, the gap between the first mass portion 21 and the first fixed electrode 11 and the gap between the second mass portion 22 and the second fixed electrode 12 are equal, so that the capacitance C1 , C2 have the same capacitance value. Further, for example, when an acceleration in the vertical direction is applied to the movable body 20 and the movable body 20 is tilted with the beam portion 25 as the rotation axis, the capacitances C1 and C2 are changed to the capacitances C1 according to the tilt of the movable body 20. , The capacitance value of C2 changes. When the movable body 20 is tilted, the gap between the first mass portion 21 and the first fixed electrode 11 and the gap between the second mass portion 22 and the second fixed electrode 12 are different, so that the capacitances C1 and C2 are different. The capacitance value of is also different.

3 to 6 are cross-sectional views schematically showing the operation of the physical quantity sensor. Here, the relationship between the operation of the physical quantity sensor and the capacitance will be described with reference to FIGS. 3 to 6. In addition, in FIGS. 3 to 6, the illustration of the configuration which is not necessary for the explanation of the operation is omitted.

FIG. 3 shows a state in which the movable body 20 is positioned substantially horizontally with respect to the support substrate 10. The case where the acceleration αu in the + Z axis direction is applied to the physical quantity sensor 100 in this state will be described.
The movable body 20 has a flat rectangular shape having a uniform thickness (dimensions in the Z-axis direction). The first movable body 20a has a mass m1, and its center of gravity G1 is located at a distance r1 in the −X axis direction from the center Q of the beam portion 25 rotatably supported by the support portion 24. The second movable body 20b has a mass m2, and its center of gravity G2 is located at a distance r2 in the + X axis direction from the center Q of the beam portion 25. The first movable body 20a has a third mass portion 23 and has a rectangular shape longer than the second movable body 20b in the X-axis direction. Therefore, the mass m1 of the first movable body 20a is heavier than the mass m2 of the second movable body 20b, and the distance r1 where the center of gravity G1 of the first movable body 20a is located is the position of the center of gravity G2 of the second movable body 20b. Longer than the distance r2.

When the acceleration αu from the −Z axis direction to the + Z axis direction is applied to the physical quantity sensor 100, the first movable body 20a is subjected to the first rotation corresponding to the product of the mass m1, the acceleration αu, and the distance r1. The moment Nu1 acts in the counterclockwise direction with the center Q of the beam portion 25 as the rotation axis. On the other hand, on the second movable body 20b, a second rotational moment Nu2 corresponding to the product of the mass m2, the acceleration αu, and the distance r2 acts in the clockwise direction with the center Q of the beam portion 25 as the rotation axis. .. The mass m1 of the first movable body 20a is heavier than the mass m2 of the second movable body 20b, and the distance r1 where the center of gravity G1 of the first movable body 20a is located is from the distance r2 where the center of gravity G2 of the second movable body 20b is located. The first rotational moment Nu1 acting on the first movable body 20a is larger than the second rotational moment Nu2 acting on the second movable body 20b.

As a result, as shown in FIG. 4, the beam portion 25 receives a torque Nu corresponding to the difference between the first rotational moment Nu1 (see FIG. 3) and the second rotational moment Nu2 (see FIG. 3). It acts in the counterclockwise direction with the center Q as the rotation axis, and the movable body 20 tilts counterclockwise. As a result, the gap between the first mass portion 21 and the first fixed electrode 11 of the first movable body 20a becomes smaller (narrower), and the static electricity formed between the first mass portion 21 and the first fixed electrode 11 The capacitance value of the capacitance C1 increases. On the other hand, the gap between the second mass portion 22 and the second fixed electrode 12 of the second movable body 20b becomes larger (wider), and the capacitance formed between the second mass portion 22 and the second fixed electrode 12 The capacitance value of C2 decreases.

FIG. 5 shows a state in which the movable body 20 is positioned substantially horizontally with respect to the support substrate 10. The case where the acceleration αd in the −Z axis direction is applied to the physical quantity sensor 100 in this state will be described.
When the acceleration αd from the + Z-axis direction to the −Z-axis direction is applied to the physical quantity sensor 100, the first movable body 20a is subjected to the first rotation corresponding to the product of the mass m1, the acceleration αd, and the distance r1. The moment Nd1 acts in the clockwise direction with the center Q of the beam portion 25 as the rotation axis. On the other hand, on the second movable body 20b, a second rotational moment Nd2 corresponding to the product of the mass m2, the acceleration αd, and the distance r2 acts in the counterclockwise direction with the center Q of the beam portion 25 as the rotation axis. do. The mass m1 of the first movable body 20a is heavier than the mass m2 of the second movable body 20b, and the distance r1 where the center of gravity G1 of the first movable body 20a is located is from the distance r2 where the center of gravity G2 of the second movable body 20b is located. The first rotational moment Nd1 acting on the first movable body 20a is larger than the second rotational moment Nd2 acting on the second movable body 20b.

As a result, as shown in FIG. 6, the beam portion 25 is provided with a torque Nd corresponding to the difference between the first rotational moment Nd1 (see FIG. 5) and the second rotational moment Nd2 (see FIG. 5). The movable body 20 tilts clockwise by acting in the clockwise direction with the center Q as the rotation axis. As a result, the gap between the first mass portion 21 and the first fixed electrode 11 of the first movable body 20a becomes large (wide), and the static electricity formed between the first mass portion 21 and the first fixed electrode 11 The capacitance value of the capacitance C1 decreases. On the other hand, the gap between the second mass portion 22 and the second fixed electrode 12 of the second movable body 20b becomes smaller (narrower), and the capacitance formed between the second mass portion 22 and the second fixed electrode 12 The capacitance value of C2 increases.

The physical quantity sensor 100 increases the torques Nu and Nd acting on the beam portion 25, that is, increases the mass difference between the first movable body 20a and the second movable body 20b, and increases the mass difference between the beam portion 25 and the first movable body 20b. By increasing the difference between the distance r1 to the center of gravity G1 of 20a and the distance r2 from the beam portion 25 to the center of gravity G2 of the second movable body 20b, the movable body 20 can be greatly tilted. As a result, the increase / decrease in the capacitance values of the capacitances C1 and C2 becomes large, so that the sensitivity for detecting the physical quantity of the physical quantity sensor 100 can be improved. Further, the physical quantity sensor 100 can increase the tilt of the movable body 20 by narrowing the width of the beam portion 25 functioning as a torsion spring in the X-axis direction and lowering the toughness of the spring. Thereby, the detection sensitivity of the physical quantity can be improved.

Next, the openings provided in the movable body and the protrusions provided in the support substrate will be described. As shown in FIGS. 1 and 2, the physical quantity sensor 100 limits the displacement of the movable body 20 in order to prevent the movable body 20 and the support substrate 10 from coming into contact with each other when an excessive acceleration is applied. The protrusion 15 is provided on the main surface 17 of the support substrate 10. The protrusions 15 are provided in a region where the support substrate 10 is spaced apart from the movable body 20 of the support substrate 10 when viewed in the direction perpendicular to the flat plate surface 28 (Z-axis direction).

In the present embodiment, a plurality of protrusions 15 (two each) are provided on the support substrate 10 in a region overlapping the first mass portion 21 and a region overlapping the second mass portion 22. The protrusion 15 has a columnar shape, and its diameter is approximately 3 to 5 μm. As a result, the end portion of the movable body 20 is prevented from colliding with the support substrate 10 and being damaged. Further, by providing a plurality of protrusions 15, the impact received when the movable body 20 and the protrusions 15 come into contact with each other can be dispersed. In the present embodiment, two protrusions 15 are provided at positions corresponding to the first and second mass parts 21 and 22, but the present invention is not limited to this. The protrusions 15 may be provided one by one or three or more by each. Further, the protrusion 15 on the side of the first movable body 20a may be provided at a position corresponding to the third mass portion 23. Further, although the shape of the protrusion has been described as having a columnar shape, it may be a polygonal prism such as a triangular prism or a quadrangular prism, or may have a chamfered upper surface. Further, an insulating protective film may be formed on the surface of the protrusion 15. This makes it possible to prevent an electrical short circuit when the first and second mass parts 21 and 22 come into contact with the protrusion 15.

On the other hand, in the movable body 20, when an acceleration in the vertical direction is applied to the movable body 20 and the movable body 20 swings, damping caused by the viscosity of the gas (a function of stopping the movement of the movable body, flow resistance) A plurality of openings 26 are provided in a direction (Z-axis direction) penetrating the flat plate surface 28 in order to reduce the problem. The opening 26 is D / outward from the outer periphery of the protrusion 15 when the maximum external dimension of the protrusion 15 is D when the support substrate 10 is viewed in the direction perpendicular to the flat plate surface 28 (Z-axis direction). It is provided in a region excluding the range 2 (the range 2D from the center of the protrusion 15). As a result, the damping of the movable body 20 is reduced and the sensitivity for detecting the physical quantity is improved.

In the present embodiment, square openings 26 are arranged in a matrix in a region excluding the 2D range from the center of the protrusion 15 in a plan view from the Z-axis direction. In other words, when an excessive acceleration is applied to the physical quantity sensor 100, the movable body 20 swings, and the opening 26 is not provided in the region where the movable body 20 and the protrusion 15 come into contact with each other.

On the contrary, when the opening 26 is also provided within the range of 2D from the center of the protrusion 15, when the grid-like frame portion 27 formed by the adjacent openings 26 and the protrusion 15 come into local contact with each other. In addition, the frame portion 27 of the movable body 20 may be easily damaged. Since the physical quantity sensor 100 of the present embodiment is not provided with the opening 26 in the region in contact with the protrusion 15, the rigidity of the region is improved. As a result, it is possible to prevent the movable body 20 from being damaged when the movable body 20 and the protrusion 15 come into contact with each other due to an excessive acceleration applied to the physical quantity sensor 100. The plurality of openings 26 may have different shapes. In addition, the position and quantity of the openings 26 can be freely set.

In the present embodiment, it has been described that the movable body 20 is provided so as to be swingable by a beam portion 25 supported via a support column 14 or the like provided on the support substrate 10. It is not limited. For example, the movable body is formed by a beam portion that surrounds the outer circumference of the movable body in a plan view from the Z-axis direction and extends in the Y-axis direction from a frame-shaped support provided at a predetermined distance from the movable body. It may be configured so as to be swingable.

<Manufacturing method of physical quantity sensor>
FIG. 7 is a flowchart illustrating a manufacturing process of the physical quantity sensor. 8 to 12 are cross-sectional views taken in each manufacturing process of the physical quantity sensor. Next, a method of manufacturing the physical quantity sensor 100 will be described with reference to FIGS. 7 to 12.

Step S1 is a support substrate forming step for forming the support substrate 10 and the protrusions 15. First, a glass substrate is prepared. In the support substrate forming step, the support substrate 10 and the protrusions 15 are formed by patterning the glass substrate using a photolithography technique and an etching technique. For example, the glass substrate can be wet-etched by using a hydrofluoric acid-based etchant. As a result, it is possible to obtain the support substrate 10 in which the concave cavity 16, the support column 14, and the protrusion 15 are formed on the glass substrate as shown in FIG.

Step S2 is a fixed electrode forming step of forming the first and second fixed electrodes 11 and 12. In the fixed electrode forming step, a conductive film is formed on the main surface 17 of the support substrate 10 by a sputtering method or the like, and then the conductive film is patterned using a photolithography technique and an etching technique (dry etching, wet etching, etc.). The first and second fixed electrodes 11 and 12 are formed. As a result, as shown in FIG. 9, the first and second fixed electrodes 11 and 12 can be provided on the main surface 17 in the cavity 16 of the support substrate 10.

Step S3 is a substrate bonding step of bonding the support substrate 10 and the silicon substrate 20S. As shown in FIG. 10, in the substrate bonding step, the support substrate 10 and the silicon substrate 20S are bonded, for example, by anode bonding, direct bonding, or using an adhesive.

Step S4 is a movable body forming step of forming the movable body 20 having the opening 26 from the silicon substrate 20S. In the movable body forming step, the silicon substrate 20S is ground using, for example, a grinder to thin the silicon substrate 20S to a predetermined thickness. Then, the movable body 20 is formed by patterning the silicon substrate 20S using a photolithography technique and an etching technique. For example, the silicon substrate 20S can be etched by a Bosch process using a RIE (Reactive Ion Etching) apparatus. As a result, as shown in FIG. 11, the movable body 20 including the opening 26, the support portion 24, and the beam portion 25 is integrally formed.

Step S5 is a sealing step of sealing the movable body 20. In the sealing step, the lid 30 is joined to the support substrate 10 and the movable body 20 is accommodated in the space formed by the support substrate 10 and the lid 30. The support substrate 10 and the lid 30 are joined by using, for example, an anode bond or an adhesive. As shown in FIG. 12, the physical quantity sensor 100 is obtained.

In the present embodiment, a method for manufacturing a physical quantity sensor 100 that forms a cavity 16 in which the movable body 20 can swing is shown on the support substrate 10. On the other hand, as a method for manufacturing a physical quantity sensor, there is also a method in which a silicon substrate on which a sacrificial layer is formed and a support substrate are joined via the sacrificial layer to form a cavity in the sacrificial layer in which a movable body can swing. In the case of this manufacturing method, after forming the movable body on the silicon substrate, the movable body is formed on the sacrificial layer by etching the sacrificial layer sandwiched between the silicon substrate and the support substrate from the opening of the movable body formed at the same time. It forms a swingable cavity. Therefore, it is necessary to provide openings in the movable body in a matrix without gaps. In other words, it was not possible to make a configuration in which an opening is not provided in the area where the movable body and the protrusion come into contact with each other.

In the manufacturing method of the present embodiment, the cavity 16 and the protrusion 15 are formed in the support substrate 10 in the support substrate forming step, the support substrate 10 and the silicon substrate 20S are joined in the substrate bonding step, and finally the movable body 20 is formed. And the opening 26 is formed. According to this manufacturing method, the opening 26 can be not provided in the region where the movable body 20 and the protrusion 15 come into contact with each other. As a result, the rigidity of the region where the movable body 20 and the protrusion 15 come into contact with each other is improved. Therefore, when the physical quantity sensor 100 is subjected to excessive acceleration and the movable body 20 and the protrusion 15 come into contact with each other, the movable body 20 is damaged. Can be suppressed. Further, since the movable body 20 is provided with the opening 26 in a region other than the range of D / 2 from the outer circumference of the protrusion 15 to the outside, the damping of the movable body 20 is reduced and the sensitivity for detecting the physical quantity is improved. ..

As described above, according to the physical quantity sensor 100 according to the present embodiment, the following effects can be obtained.
The physical quantity sensor 100 has a protrusion 15 protruding from the support substrate 10 toward the movable body 20. Further, the movable body 20 is provided with a plurality of openings 26 penetrating the flat plate surface 28. The protrusions 15 are provided in a region where the support substrate 10 is spaced apart from the movable body 20 of the support substrate 10 when viewed in the direction perpendicular to the flat plate surface 28. The opening 26 is provided in a region excluding the range 2D from the center of the protrusion 15 when the support substrate 10 is viewed in the direction perpendicular to the flat plate surface 28 and the maximum external dimension of the protrusion 15 is D. .. In other words, the opening 26 is not provided in the range 2D from the center of the protrusion 15, that is, at the position where it comes into contact with the protrusion 15. As a result, the rigidity of the region is improved, so that it is possible to prevent the movable body 20 from being damaged when the movable body 20 and the protrusion 15 come into contact with each other. Further, the damping received by the movable body 20 is reduced by the plurality of openings 26 provided in a range excluding 2D from the center of the protrusion 15, so that the detection sensitivity of the physical quantity sensor 100 is improved. Therefore, it is possible to provide the physical quantity sensor 100 with improved reliability and detection sensitivity.

Further, since a plurality of protrusions 15 projecting from the support substrate 10 toward the movable body 20 are provided, the impact received when the movable body 20 comes into contact with the protrusions 15 can be dispersed.

The manufacturing method of the physical quantity sensor 100 includes a support substrate forming step of forming the support substrate 10 and the protrusion 15, a substrate bonding step of joining the support substrate 10 and the silicon substrate 20S, and forming a movable body 20 having an opening 26 from the silicon substrate 20S. Includes a movable body forming step. In this manufacturing method, after forming the cavity 16 and the protrusion 15 in the support substrate 10 in the support substrate forming step, the support substrate 10 and the silicon substrate 20S are joined in the substrate bonding step, and finally the movable body 20 and the opening 26 are joined. To form. According to this manufacturing method, the opening 26 can be not provided in the region where the movable body 20 and the protrusion 15 come into contact with each other (the region 2D from the center of the protrusion 15). As a result, the rigidity of the region is improved, so that it is possible to prevent the movable body 20 from being damaged when the movable body 20 and the protrusion 15 come into contact with each other. Further, the damping received by the movable body 20 is reduced by the plurality of openings 26 provided in the region excluding the 2D range from the center of the protrusion 15, so that the detection sensitivity of the physical quantity sensor 100 is improved. Therefore, it is possible to provide a method for manufacturing the physical quantity sensor 100 that improves reliability and detection sensitivity.

The present invention is not limited to the above-described embodiment, and various changes and improvements can be added to the above-described embodiment.

(Modification example)
FIG. 13 is a plan view schematically showing the physical quantity sensor according to the modified example. FIG. 14 is a cross-sectional view taken along the line BB in FIG. Hereinafter, the physical quantity sensor 200 according to the first modification will be described. The same reference numerals are used for the same constituent parts as those in the embodiment, and duplicate description will be omitted. In the physical quantity sensor 200 of this modified example, the positions of the protrusions 215 are different from those of the physical quantity sensor 100 described in the embodiment.

As shown in FIGS. 13 and 14, the physical quantity sensor 200 limits the displacement of the movable body 20 in order to prevent the movable body 20 and the support substrate 10 from coming into contact with each other when an excessive acceleration is applied. The protrusion 215 is provided on the main surface 17 of the support substrate 10. The protrusion 215 is within 1/2 of the distance Ra between the center line CL2 of the beam portion 25 and the end portion of the movable body 20 in the X-axis direction intersecting the axial direction (Y-axis direction) of the beam portion 25 as the rotation axis. It is provided in.

Specifically, in this modification, two protrusions 215 are provided on the support substrate 10 in a region overlapping the first mass portion 21 and a region overlapping the second mass portion 22. The protrusion 215 overlapping the first mass portion 21 is provided at a position separated by a distance R1 in the −X axis direction from the center line CL2. The distance R1 between the center line CL2 and the protrusion 215 is shorter than 1/2 of the distance Ra between the center line CL2 and the end of the first movable body 20a. The protrusion 215 overlapping the second mass portion 22 is provided at a position separated by a distance R2 in the + X axis direction from the center line CL2. The distance R2 between the center line CL2 and the protrusion 215 is shorter than 1/2 of the distance Rb between the center line CL2 and the end of the second movable body 20b. In this modification, the distance R1 and the distance R2 are set to the same distance. That is, the protrusions 215 are provided line-symmetrically with respect to the center line CL2.

Since the moving speed of the movable body 20 increases as the distance from the center of the beam portion 25 (center line CL2) increases, the damping received by the movable body 20 increases toward the end of the movable body. The region where the opening 26 is not provided (the range of 2D from the center of the protrusion 215) corresponding to the protrusion 215 of this modification is within the distance Ra / 2 and within the distance Rb / 2 where the influence of damping is small in the X-axis direction. Since it is located on the beam portion 25 side of the movable body 20, the damping received by the movable body 20 can be further reduced.

Further, the protrusion 215 is provided at a position of a distance R3 symmetrical with respect to the center line CL1 that divides the movable body 20 into two equal parts in the axial direction (Y-axis direction) of the beam portion 25 as the rotation axis. As a result, it is possible to prevent the movable body 20 from being damaged due to the twisting of the movable body 20 when the movable body 20 and the protrusion 215 come into contact with each other.

(Composite sensor)
Next, with reference to FIG. 15, a configuration example of the composite sensor including the above-mentioned physical quantity sensors 100 and 200 will be described. FIG. 15 is a functional block diagram showing a schematic configuration of the composite sensor. In the following, an example using the physical quantity sensor 100 will be described.

As shown in FIG. 15, the composite sensor 900 includes a physical quantity sensor 100 which is an acceleration sensor for measuring acceleration in the Z-axis direction as described above, and a physical quantity which is an acceleration sensor for measuring acceleration in the X-axis direction. It includes a sensor 101, a physical quantity sensor 102 which is an acceleration sensor for measuring acceleration in the Y-axis direction, and an angular velocity sensor 103. The angular velocity sensor 103 can efficiently and accurately detect the required angular velocity in the uniaxial direction. The angular velocity sensor 103 may also include three angular velocity sensors 103 corresponding to the respective axial directions in order to measure the angular velocity in the three axial directions. Further, the composite sensor 900 includes, for example, an X-axis, a Y-axis, and a drive circuit for driving the physical quantity sensors 100, 101, 102 and the angular velocity sensor 103, and the X-axis, the Y-axis, and the composite sensor 900 based on the signals from the physical quantity sensors 100, 101, 102 and the angular velocity sensor 103. An IC 40a including a detection circuit (signal processing unit 45a) for detecting acceleration and angular velocity in each axis direction of the Z axis, an output circuit (output unit 46a) for converting a signal from the detection circuit into a predetermined signal, and the like. Can be prepared.

The composite sensor 900 can be easily configured by the physical quantity sensors 100, 101, 102 and the angular velocity sensor 103, and a plurality of physical quantity data such as acceleration data and angular velocity data can be easily acquired by one sensor. ..

(Inertial measurement unit)
Next, an inertial measurement unit (IMU) will be described with reference to FIGS. 16 and 17. FIG. 16 is an exploded perspective view showing a schematic configuration of the inertial measurement unit. FIG. 17 is a perspective view showing an arrangement example of the inertial sensor element of the inertial measurement unit. In the following, an example using the physical quantity sensor 100 will be described.

As shown in FIG. 16, the inertial measurement unit 3000 is composed of an outer case 301, a joining member 310, a sensor module 325 including an inertial sensor element, and the like. In other words, the sensor module 325 is integrated (inserted) by interposing the joining member 310 in the inner 303 of the outer case 301. The sensor module 325 is composed of an inner case 320 and a substrate 315. In order to make the explanation easier to understand, the part names are the outer case and the inner case, but they may be referred to as the first case and the second case.

The outer case 301 is a pedestal made by carving out aluminum into a box shape. The material is not limited to aluminum, and other metals such as zinc and stainless steel, resin, or a composite material of metal and resin may be used. The outer shape of the outer case 301 is a rectangular parallelepiped whose plane shape is substantially square, similar to the overall shape of the inertial measurement unit 3000 described above, and through holes (stupid holes) are provided in the vicinity of two vertices located in the diagonal direction of the square. ) 302 is formed. The notch is not limited to the through hole (stupid hole) 302, and for example, a notch that can be screwed with a screw (a notch is provided at the corner of the outer case 301 where the through hole (stupid hole) 302 is located. The structure to be formed) may be formed and screwed, or a flange (ear) may be formed on the side surface of the outer case 301 and the flange portion may be screwed.

The outer case 301 has a rectangular parallelepiped outer shape and is box-shaped without a lid, and its inner 303 (inside) is an internal space (container) surrounded by a bottom wall 305 and a side wall 304. In other words, the outer case 301 has a box shape with one surface facing the bottom wall 305 as an opening surface, and the sensor module so as to cover most of the opening of the opening surface (so as to close the opening). The 325 is housed and the sensor module 325 is exposed from the opening (not shown). Here, the opening surface facing the bottom wall 305 is the same surface as the upper surface 307 of the outer case 301. Further, the planar shape of the inner 303 of the outer case 301 is a hexagon in which the corners of the two apex portions of the square are chamfered, and the two chamfered apex portions correspond to the positions of the through holes (stupid holes) 302. There is. Further, in the cross-sectional shape (thickness direction) of the inner 303, the bottom wall 305 is formed with a first joint surface 306 as the inner 303, that is, a bottom wall one step higher than the central portion at the peripheral edge portion in the internal space. .. That is, the first joint surface 306 is a part of the bottom wall 305, and is a one-step stepped portion formed in a ring shape around the central portion of the bottom wall 305 in a plane, and is more than the bottom wall 305. It is a surface having a small distance from the opening surface (the same surface as the upper surface 307).

Although an example has been described in which the outer shape of the outer case 301 is a polygon having a substantially square plane shape and a box shape without a lid, the outer shape of the outer case 301 is not limited to this, and the outer plane shape of the outer case 301 is, for example, a hexagon or eight. It may be a polygon such as a polygon, the corners of the apex portion of the polygon may be chamfered, or it may be a planar shape in which each side is a curve. Further, the planar shape of the inside 303 (inside) of the outer case 301 is not limited to the hexagon described above, and may be a square (quadrangle) such as a square or another polygon such as an octagon. Further, the outer shape of the outer case 301 and the plane shape of the inner 303 may or may not be similar figures.

The inner case 320 is a member that supports the substrate 315, and has a shape that fits inside 303 of the outer case 301. Specifically, in terms of plane, it is a hexagon with the corners of the two apex portions of the square chamfered, and an opening 321 which is a rectangular through hole and a surface on the side supporting the substrate 315 are provided in the hexagon. A recess 331 is formed. The two chamfered vertices correspond to the positions of the through holes (stupid holes) 302 of the outer case 301. The height in the thickness direction (Z-axis direction) is lower than the height from the upper surface 307 of the outer case 301 to the first joint surface 306. In a preferred example, the inner case 320 is also formed by carving out aluminum, but other materials may be used as in the outer case 301.

A guide pin for positioning the substrate 315 and a support surface (neither of which is shown) are formed on the back surface of the inner case 320 (the surface on the outer case 301 side). The substrate 315 is set (positioned and mounted) on the guide pin or the support surface and adhered to the back surface of the inner case 320. The details of the substrate 315 will be described later. The peripheral edge of the back surface of the inner case 320 is a second joint surface 322 formed of a ring-shaped flat surface. The second joint surface 322 has substantially the same shape as the first joint surface 306 of the outer case 301 in a plane, and when the inner case 320 is set on the outer case 301, the joint member 310 is sandwiched between the second joint surface 322. The two sides will face each other. The structure of the outer case 301 and the inner case 320 is an embodiment and is not limited to this structure.

The configuration of the substrate 315 on which the inertial sensor is mounted will be described with reference to FIG. As shown in FIG. 17, the substrate 315 is a multilayer substrate in which a plurality of through holes are formed, and a glass epoxy substrate (Galaepo substrate) is used. The board is not limited to the Gala Epo board, but may be a rigid board on which a plurality of inertial sensors, electronic components, connectors, etc. can be mounted. For example, a composite substrate or a ceramic substrate may be used.

On the surface of the substrate 315 (the surface on the inner case 320 side), an acceleration detection unit 1 including a connector 316, an angular velocity sensor 317z, and a physical quantity sensor 100 which is an acceleration sensor for measuring the acceleration in the Z-axis direction described above is mounted. Has been done. The connector 316 is a plug-type (male) connector, and includes two rows of connection terminals arranged at equal pitches in the X-axis direction. Preferably, the connection terminals are 10 pins in a row and 20 pins in a total of two rows, but the number of terminals may be appropriately changed according to the design specifications.

The angular velocity sensor 317z as an inertial sensor is a gyro sensor that detects the angular velocity of one axis in the Z-axis direction. As a preferred example, a crystal is used as a vibrator, and a vibration gyro sensor that detects the angular velocity from the Coriolis force applied to a vibrating object is used. The sensor is not limited to the vibration gyro sensor, and may be a sensor capable of detecting the angular velocity. For example, a sensor using ceramic or silicon may be used as the vibrator.

Further, on the side surface of the substrate 315 in the X-axis direction, an angular velocity sensor 317x that detects the angular velocity of one axis in the X-axis direction is mounted so that the mounting surface (mounting surface) is orthogonal to the X-axis. Similarly, an angular velocity sensor 317y for detecting the angular velocity of one axis in the Y-axis direction is mounted on the side surface of the substrate 315 in the Y-axis direction so that the mounting surface (mounting surface) is orthogonal to the Y-axis.

The angular velocity sensors 317x, 317y, and 317z are not limited to the configuration in which three angular velocity sensors are used for each of the X-axis, Y-axis, and Z-axis axes, and any sensor that can detect the angular velocity of the three axes may be used. For example, a sensor device capable of detecting (detecting) the angular velocities of three axes with one device (package) may be used.

The acceleration detection unit 1 includes at least a physical quantity sensor 100 which is an acceleration sensor for measuring the acceleration in the Z-axis direction described above, and accelerates in a uniaxial direction (for example, in the Z axis direction) or in a biaxial direction as necessary. (For example, Z-axis, Y-axis, or X-axis, Y-axis) and triaxial direction (X-axis, Y-axis, Z-axis) acceleration can be detected.

A control IC 319 as a control unit is mounted on the back surface of the substrate 315 (the surface on the outer case 301 side). The control IC 319 is an MCU (Micro Controller Unit), and has a built-in storage unit including a non-volatile memory, an A / D converter, and the like, and controls each unit of the inertial measurement unit 3000. The storage unit stores a program that defines the order and contents for detecting acceleration and angular velocity, a program that digitizes detection data and incorporates it into packet data, and accompanying data. In addition, a plurality of other electronic components are mounted on the substrate 315.

According to such an inertial measurement unit 3000, since the acceleration detection unit 1 including the physical quantity sensor 100 is used, it is possible to provide the inertial measurement unit 3000 having excellent impact resistance and improved reliability.

(Portable electronic device)
Next, the portable electronic device using the physical quantity sensors 100 and 200 will be described in detail with reference to FIGS. 18 and 19. In the following, an example using the physical quantity sensor 100 will be described. Hereinafter, a wristwatch-type activity meter (active tracker) will be described as an example of a portable electronic device.

As shown in FIG. 18, the wrist device 2000, which is a wristwatch-type activity meter (active tracker), is attached to a part (subject) such as a user's wrist by bands 62, 67, etc., and displays a digital display unit 150. It is possible to prepare and wirelessly communicate. The physical quantity sensor 100 according to the present invention described above is incorporated in the wrist device 2000 as one of a sensor for measuring acceleration and a sensor for measuring angular velocity.

The wrist device 2000 is housed in a case 60 in which at least the physical quantity sensor 100 is housed, a processing unit 190 (see FIG. 19) housed in the case 60 and processing output data from the physical quantity sensor 100, and a case 60. The display unit 150 and the translucent cover 71 that closes the opening of the case 60 are provided. A bezel 78 is provided on the outside of the case 60 of the translucent cover 71 of the case 60. A plurality of operation buttons 80 and 81 are provided on the side surface of the case 60. Hereinafter, a more detailed description will be given with reference to FIG.

The acceleration sensor 113 including the physical quantity sensor 100 detects each acceleration in the three-axis directions intersecting (ideally orthogonal to each other), and signals according to the magnitude and direction of the detected three-axis acceleration (acceleration signal). ) Is output. Further, the angular velocity sensor 114 detects each angular velocity in the triaxial directions intersecting (ideally orthogonal to each other), and outputs a signal (angular velocity signal) according to the magnitude and direction of the detected triaxial angular velocity. ..

In the liquid crystal display (LCD) constituting the display unit 150, for example, the position information using the GPS sensor 110 or the geomagnetic sensor 111, the acceleration sensor 113 included in the movement amount or physical quantity sensor 100, or the angular velocity is used according to various detection modes. Exercise information such as the amount of exercise using the sensor 114 or the like, biological information such as the pulse rate using the pulse sensor 115 or the like, or time information such as the current time is displayed. It is also possible to display the environmental temperature using the temperature sensor 116.

The communication unit 170 performs various controls for establishing communication between the user terminal and an information terminal (not shown). The communication unit 170 is, for example, Bluetooth (registered trademark) (BTLE: including Bluetooth Low Energy), Wi-Fi (registered trademark) (Wireless Fidelity), Zigbee (registered trademark), NFC (Near field communication), ANT + (registered). A transmitter / receiver and a communication unit 170 corresponding to a short-range wireless communication standard such as a trademark) are configured to include a connector corresponding to a communication bus standard such as USB (Universal Serial Bus).

The processing unit 190 (processor) is composed of, for example, an MPU (Micro Processing Unit), a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), or the like. The processing unit 190 executes various processes based on the program stored in the storage unit 140 and the signals input from the operation units 120 (for example, the operation buttons 80 and 81). The processing by the processing unit 190 includes data processing for each output signal of the GPS sensor 110, the geomagnetic sensor 111, the pressure sensor 112, the acceleration sensor 113, the angular velocity sensor 114, the pulse sensor 115, the temperature sensor 116, and the timing unit 130, and the display unit 150. Display processing that displays an image on the sensor, sound output processing that outputs sound to the sound output unit 160, communication processing that communicates with an information terminal (not shown) via the communication unit 170, and power from the battery 180 is supplied to each unit. Includes power control processing and the like.

Such a wrist device 2000 can have at least the following functions.
1. 1. Distance: The total distance from the start of measurement is measured by the high-precision GPS function.
2. Pace: Displays the current running pace from the pace distance measurement.
3. 3. Average speed: Average speed Calculates and displays the average speed from the start of running to the present.
4. Elevation: The GPS function measures and displays the altitude.
5. Stride: Measures and displays stride length even in tunnels where GPS radio waves do not reach.
6. Pitch: Measures and displays the number of steps per minute.
7. Heart rate: The heart rate is measured and displayed by the pulse sensor.
8. Gradient: Measures and displays the slope of the ground during training and trail running in the mountains.
9. Auto lap: Automatically measures laps when running a preset distance or time.
10. Exercise calories burned: Shows calories burned.
11. Steps: Displays the total number of steps since the start of exercise.

The wrist device 2000 can be widely applied to a running watch, a runner's watch, a runner's watch compatible with multi-sports such as duathlon and triathlon, an outdoor watch, and a satellite positioning system, for example, a GPS watch equipped with GPS.

Further, in the above description, GPS (Global Positioning System) has been used as the satellite positioning system, but another Global Navigation Satellite System (GNSS) may be used. For example, one or more of satellite positioning systems such as EGNOS (European Geostationary-Satellite Navigation Overlay Service), QZSS (Quasi Zenith Satellite System), GLONASS (GLObal NAvigation Satellite System), GALILEO, BeiDou (BeiDou Navigation Satellite System), etc. May be used. In addition, at least one of the satellite positioning systems uses a geostationary satellite navigation reinforcement system (SBAS: Satellite-based Augmentation System) such as WAAS (Wide Area Augmentation System) and EGNOS (European Geostationary-Satellite Navigation Overlay Service). May be good.

Since such a portable electronic device (wrist device 2000) includes a physical quantity sensor 100 and a processing unit 190, it has excellent reliability such as impact resistance.

(Electronics)
Next, the electronic device provided with the physical quantity sensors 100 and 200 according to the embodiment of the present invention will be described with reference to FIGS. 20 to 22. In the following, an example using the physical quantity sensor 100 will be described.

FIG. 20 is a perspective view showing a schematic configuration of a mobile (or notebook) personal computer as an electronic device including a physical quantity sensor according to an embodiment of the present invention. In this figure, the personal computer 1100 is composed of a main body 1104 having a keyboard 1102 and a display unit 1106 having a display 1000, and the display unit 1106 swings with respect to the main body 1104 via a hinge structure. It is movably supported. Such a personal computer 1100 has a built-in physical quantity sensor 100 that functions as an acceleration sensor or the like, and a control unit (not shown) controls, for example, attitude control based on a detection signal from the physical quantity sensor 100. be able to.

FIG. 21 is a perspective view showing a schematic configuration of a mobile phone (including PHS) as an electronic device including a physical quantity sensor according to an embodiment of the present invention. In this figure, the mobile phone 1200 includes a plurality of operation buttons 1202, an earpiece 1204, and a mouthpiece 1206, and a display unit 1000 is arranged between the operation button 1202 and the earpiece 1204. Such a mobile phone 1200 has a built-in physical quantity sensor 100 that functions as an acceleration sensor or the like, and a control unit (not shown) can be, for example, the posture of the mobile phone 1200 or the like based on a detection signal from the physical quantity sensor 100. By recognizing the behavior, the display image displayed on the display unit 1000 can be changed, a warning sound or a sound effect can be sounded, or a vibration motor can be driven to vibrate the main body.

FIG. 22 is a perspective view showing a schematic configuration of a digital still camera as an electronic device including a physical quantity sensor according to an embodiment of the present invention. Note that this figure also briefly shows the connection with an external device. Here, while the conventional film camera sensitizes the silver halide photographic film by the light image of the subject, the digital still camera 1300 photoelectrically converts the light image of the subject by an image sensor such as a CCD (Charge Coupled Device). To generate an image pickup signal (image signal).
A display unit 1000 is provided on the back surface of the case (body) 1302 of the digital still camera 1300, and is configured to display based on an image pickup signal by a CCD. The display unit 1000 displays a subject as an electronic image. Functions as a finder. Further, on the front side (back side in the drawing) of the case 1302, a light receiving unit 1304 including an optical lens (imaging optical system), a CCD, and the like is provided.
When the photographer confirms the subject image displayed on the display unit 1000 and presses the shutter button 1306, the image pickup signal of the CCD at that time is transferred and stored in the memory 1308. Further, in the digital still camera 1300, a video signal output terminal 1312 and an input / output terminal 1314 for data communication are provided on the side surface of the case 1302. Then, as shown in the figure, a television monitor 1430 is connected to the video signal output terminal 1312, and a personal computer 1440 is connected to the input / output terminal 1314 for data communication, respectively, as needed. Further, the imaging signal stored in the memory 1308 is output to the television monitor 1430 and the personal computer 1440 by a predetermined operation. Such a digital still camera 1300 has a built-in physical quantity sensor 100 that functions as an acceleration sensor or the like, and a control unit (not shown) controls control such as camera shake correction based on a detection signal from the physical quantity sensor 100. Can be done.

The electronic devices 1100, 1200, and 1300 as described above include a physical quantity sensor 100 capable of improving reliability and detection sensitivity. As a result, the electronic devices 1100, 1200, 1300 can have high reliability and detection sensitivity.

The physical quantity sensor 100 according to the embodiment of the present invention includes, for example, an inkjet type, in addition to the personal computer 1100 (mobile personal computer) of FIG. 20, the mobile phone 1200 of FIG. 21, and the digital still camera 1300 of FIG. Discharge device (for example, inkjet printer), laptop personal computer, TV, video camera, VCR, car navigation device, pager, electronic notebook (including communication function), electronic dictionary, calculator, electronic game equipment, word processor, Workstations, VCRs, security TV monitors, electronic binoculars, POS terminals, medical equipment (eg electronic thermometers, blood pressure monitors, blood glucose meters, electrocardiogram measuring devices, ultrasonic diagnostic devices, electronic endoscopes), fish finder, various types It can be applied to electronic devices such as measuring devices, instruments (for example, instruments for vehicles, aircraft, and ships), flight simulators, and the like.

(Mobile)
Next, a moving body including the physical quantity sensors 100 and 200 according to the embodiment of the present invention will be described with reference to FIG. 23. In the following, an example using the physical quantity sensor 100 will be described.
FIG. 23 is a perspective view schematically showing an automobile as a moving body including a physical quantity sensor according to an embodiment of the present invention. The physical quantity sensor 100 according to the embodiment is mounted on the automobile 1500. For example, as shown in FIG. 23, in the automobile 1500 as a moving body, an electronic control unit 1510 as a control unit for controlling tires and the like with a built-in physical quantity sensor 100 is mounted on the vehicle body. In addition, the physical quantity sensor 100 also includes a keyless entry, an immobilizer, a car navigation system, a car air conditioner, an anti-lock braking system (ABS), an airbag, a tire pressure monitoring system (TPMS), and an engine. It can be widely applied to electronic control units (ECUs: Electronic Control Units) such as controls, battery monitors for hybrid vehicles and electric vehicles, and vehicle body attitude control systems.

10 ... Support substrate, 11 ... First fixed electrode, 12 ... Second fixed electrode, 14 ... Support, 15,215 ... Projection, 16 ... Cavity, 17 ... Main surface, 20 ... Movable body, 20S ... Silicon substrate, 20a ... 1st movable body, 20b ... 2nd movable body, 21 ... 1st mass part, 22 ... 2nd mass part, 23 ... 3rd mass part, 24 ... support part, 25 ... beam part, 26 ... opening, 27 ... frame Part, 28 ... Flat plate surface, 30 ... Lid, 100, 200 ... Physical quantity sensor, 900 ... Composite sensor, 1100 ... Personal computer, 1200 ... Mobile phone, 1300 ... Digital still camera, 1500 ... Automobile, 2000 ... Portable electronic device As a wrist device, 3000 ... inertial measurement unit.

Claims (11)

A movable body that is flat, has a plurality of openings in a direction penetrating the flat flat surface, and can swing around a rotation axis.
A support substrate formed by connecting a part of the flat plate surface with a support column in order to support the movable body with a gap from the flat plate surface.
When the support substrate is viewed in a direction perpendicular to the flat plate surface, a protrusion provided so as to project toward the movable body in a region of the support substrate that overlaps the movable body with a gap.
Including
When the support substrate is viewed in the direction perpendicular to the flat plate surface, when the maximum external dimension of the protrusion is D, the opening excludes the range of D / 2 from the outer circumference of the protrusion to the outside. By being provided in the region, the movable body has a region in which the opening is not provided.
Since the protrusions are provided line-symmetrically with respect to the rotation axis, the opening is provided.
A physical quantity sensor characterized in that the non-region is provided line-symmetrically with respect to the rotation axis. The physical quantity sensor according to claim 1, wherein a plurality of the protrusions are provided. The physical quantity sensor according to claim 1 or 2, wherein the protrusions are provided symmetrically with respect to a center line that divides the movable body into two equal parts in the axial direction of the rotation axis. Claims 1 to claim that the protrusion is provided within 1/2 of the distance between the rotating shaft and the end of the movable body in a direction intersecting the axial direction of the rotating shaft. The physical quantity sensor according to any one of 3. A movable body that can swing around the axis of rotation,
A plurality of openings provided in a direction penetrating the movable body, and
A support substrate connected to a part of the movable body by a support column,
A protrusion provided on the support substrate so as to project toward the movable body in a region overlapping the movable body with a gap.
Including
When the maximum external dimension of the protrusion is D, the movable body is provided with the opening because the plurality of openings are provided in a region excluding the range of D / 2 from the outer circumference of the protrusion to the outside. and others
Has an area that is not
Since the protrusions are provided line-symmetrically with respect to the rotation axis, the opening is provided.
A physical quantity sensor characterized in that the non-region is provided line-symmetrically with respect to the rotation axis. A movable body that is flat, has a plurality of openings in a direction penetrating the flat plate surface, and can swing around a rotation axis, and supports the movable body with a gap from the flat surface. Therefore, when the support substrate is connected to a part of the flat plate surface by a support column and the support substrate is viewed in the direction perpendicular to the flat plate surface, the support substrate is separated from the movable body of the support substrate. When the overlapping region includes a protrusion provided so as to project toward the movable body side, and the maximum external dimension of the protrusion is D when the support substrate is viewed in the direction perpendicular to the flat plate surface, the opening, said from the outer periphery of the protrusion toward the outside by being provided in a region except for the range of D / 2, wherein
The movable body has a region where the opening is not provided, and the protrusion is line-symmetrical with respect to the rotation axis.
The region where the opening is not provided is line-symmetrical with respect to the rotation axis.
It is a manufacturing method of the physical quantity sensor provided in
A support substrate forming step for forming the support substrate and the protrusions,
Wafer bonding step of joining the support substrate and the silicon substrate,
A movable body forming step of forming the movable body having the opening from the silicon substrate,
A method for manufacturing a physical quantity sensor, which comprises. The physical quantity sensor according to any one of claims 1 to 5.
Angular velocity sensor and
A composite sensor characterized by being equipped with. The physical quantity sensor according to any one of claims 1 to 5.
Angular velocity sensor and
A control unit that controls the physical quantity sensor and the angular velocity sensor,
Inertial measurement unit characterized by being equipped with. The physical quantity sensor according to any one of claims 1 to 5.
The case where the physical quantity sensor is housed and
A processing unit housed in the case and processing output data from the physical quantity sensor,
The display unit housed in the case and
A translucent cover that closes the opening of the case,
A portable electronic device characterized by being equipped with. The physical quantity sensor according to any one of claims 1 to 5.
A control unit that controls based on the detection signal output from the physical quantity sensor,
An electronic device characterized by being equipped with. The physical quantity sensor according to any one of claims 1 to 5.
A control unit that controls based on the detection signal output from the physical quantity sensor,
A mobile body characterized by being equipped with.

Images